Capturing keyboard events

I am building a rails application in which it would be pretty cool to
have certain actions that occur on key presses via some javascript doing
a remote action call. I was hoping that someone who knew a little bit
about using javascript to capture key events and the different browser
issues I might encounter could share some knowledge. Which browsers
work well for this sort of thing? Can I write cross browser code or is
implementation going to be browser specific? Is it possible to do
multi-key combinations like ‘Alt+Shift+[’ ? Can I override key combos
like ‘Crtl+f’ that are often used for browser actions?

Thank you,
Matthew M.